Pipe perforator



'W. L. CHURCH PIPE PERFORATOR Aug. 2, 1938.

Filed Feb. 24, 1956 j j f1. fk

Patented Aug. 2,1938

p 2,125,487 mernarona'ron Walter L Church, Houston, Tex.

This invention relates to a `pipe perforator. An object of the invention is to provide a perforator of the character described adapted to belowered into a well for the purpose of-perforating B the pipe 'or casing set in the well opposite stratum supposed to contain oil or other iluid to berecovered. v

Another object of the invention is to -provide a perforator of the character described equipped l with a self-contained ring apparatus. thus dispensing with the necessity of carryingthe elecf trical conductor ,to-the ground surface.

Electrical perforating apparatus heretofore employed is equipped with an electrical current conductorfusually enclosed within a cable. from 'the ground surface down to the perforating appav ratus. It'has been proven very dilcult to maintain the conductor properly insulated when considerable depth has been reached. It is a prime object of this invention to provide apparatus of this character which is self-contained, that is, wherein the source of electrical supply is contained in a unit with the firing apparatus, and from which an electrical current may be ccmpleted through the explosive charge at will.

, Another object of the invention is to provide perforating apparatus of the character described `which eliminates the danger accompanyingapparatus of this type wherein the explosive charges .$0 are mechanically ignited. i

It is a further vobject to provide apparatus of thisgeneral character which is` of very simple construction, may be cheaply and easily produced, and safely used, which is very elcient for the 85 purpose intended, and which will not be substantially injured by use so that vit can be reloaded and reused from time to time.

With the above and -other objects in view, the invention has particular relation to certain novel 'e0 features of construction, operation and arrangement of parts, an example of which is given in this specication and illustrated in the accompanying drawing,'wherein: u

Figure I showsa side elevation ofthe complete 46 apparatus, shown in the well pipe to 'be perforated.

Figure 2 shows a vertical, sectionaly view of the upper end thereof. A Figure 3 shows'a side view, partly in section, of 50A an intermediate portion thereof.

Figure 4 shows a side elevation of the lower end thereof, and, y"Flgure 5 shows a cross-sectional view taken o the line 5 5 of Figure 3. Y

551. Referring now more particularly tothe draw- 24,., 193s, serial No'. 65.405

(c1. leu-aar ing wherein like numerals of reference designate similar parts in each of the figures, the numeral I designates the body of the perforator which is formed of'substantially solid metal and whose lower 'end `is tapered, as at 2, to form a guide. I Secured to the upper end of the body there is a tubular housing 3 and connected to the upper end of thishousing there is a cylinder 4 whose jupper end ls closed and formed with a reduced neck 5 provided with the external, downwardly B pitched teeth 6. A manipulating cable i has its lower end suitably secured in a socket whereby the apparatus may be lowered into and withdrawn from a well. The lower portion of the housing 3 is inwardly thickened forming an internal, annu- 1B lar shoulder-8, and seated on the shoulder there is an anchors formed of insulating-material. A supporting sleeve I0 -has its lower end secured on the anchor 9 and upstands in the housing 3. This sleeve has the'inside contact rings II therea. in and spaced. apart from the upper end thereof downwardly.` Enclosed within the housing 3 and seated on the upper end of the body i, there are the electrical batteries I2, electrically connected in series and grounded, and^a1so electrically con- 25 nected to the contactl rod lwhich extends axially upwardly through the `anchor 9 and sleeve Ill. Fitted within the cylinder 4 there is a plunger I4 having the surrounding packing I5 and internal socket I6 at its upper end with ports leading from said socket into the groove in which the packing `is seated around the piston. The piston has a tubular depending stem luwhich may be formed lintegrally therewith. said stem being formed of insulating material and working through a gland I9-in the lower end of the cylinder.

A coil spring-20 surrounds the stem I8 and is seated on the gland I Sand normally holds the 'piston I4 in its upper position.

On the lower end of the stem I8 there is a 49 metal contact preferably in the form of a cap 2|. The upper end of the rod I3 worksthrough said pap and is in constant contact therewith. The cap 2| carries the outwardly curved iiexible contact fingers 22 adapted to contact successively a with the rings II as the plunger I4 is moved downwardly. The'neck 5 has a channel Z3 leading downwardly therethrough from the upper end thereof into the socket I6 and the upper end of the channel is enclosed by a hollow cap 24 5. of frangible material which projects above the upper end of, the neck 5 and is, therefore, exposed to the impact of a weight 26 which,vat the proper time may b e slipped over the upper end of the cable 1 and dropped into the well and s.

and will be forced downwardly overcoming theV resistance of the spring 2'0 and carrying the ngers `Siti 22 successively into contact with the rings ii,`

as hereinabove indicated..

v'Suitable electrical current conductors t7 are connected at their upper ends to the respective rings ii, and they Pass through bores in the inwardly thickened portion of the housing d which continue on throughout the body i, and these conductors are insulated from the housing and terminate in oblong recesses such as 2d which are cut in the external surface of the body i and which may be covered `after the electrical connections have been'made by a cover plate te which may be welded in place and which has a removable plug S screwedinto place so that it may be readily removed for access to the cnclosed electrical connections. A

Opposite therecesses 28 there are the deep bores 3i formed in the body i whose outer ends are enlarged and threaded to receive the plugs, as 32. These plugs are arranged along and around the body i, as shown: each plug has a. central opening 33 into the innerends of which arescrewed soft metal bushings, as it, into which the projectiles 35 are screwed. The outer ends of these projectiles are pointed and are preferably formed of hard metal-such as steel. Before theplugs 32 are screwed in place, cartons, astd, containing an explosive, are inserted in the bores 3i. These cartons have' the contacts 31, 38, connected'by an electrical' conducting'element 39. and the lower ends of the conductors 21 have contacts di) arranged to contact with the corresponding contact points 38. The contacts Stare suitably insulated from the housing 3 and grounded.

.When the apparatus is located at the desired piace in the weil opposite the stratum thought. to contain oil, the weight E@ may be dropped, as hereinabove explained, to break the cap 2d and thereupon the plunger it and stem it. will be forced downwardly by the pressure of the fluid, carrying the iingers 22 successively into contact with the rings Il from above-downwardly. When said fingers contact with a ring il, an electrical circuit will be completed'through the corresponding conductor 39 which will thereupon become sumciently hot to ignite the explosive charge 3B through which it extends. This charge 1s pref-- erably'a slow explosive and pressure will be builtI up behind the projectile 35 sumcient to strip the threads of the corresponding bushings 3d, and thereupon the projectile will be ejected with sufilcient force to penetrate the ordinary pipe or pipes in the well within whichvthe apparatus is located. i f l As the plunger moves downwardly, the projectiles will be thus ejectedfone' at a time, and the well pipe will be thus perforated throughout the length of the body i, and all the way around. Thereupon the `apparatus .may be withdrawn from the well and reloaded for further use and a.

new cap 2t installed and the apparatus will then be in readiness for another Awell-shooting operation. v Y l 'Ordinarily the apparatus'niay `be withdrawn from the well by the cable l, but incase said cable should become broken,- a'cablel cutter, commonly used, may be run into the well and the cable cut on closely above the upper end ofthe apparatus charges.

pipe perorator shaped to be lowered into ranged to 4. A perforator shaped tol be lowered into a Aing elements 'to be lowered with the body into A body. electrical contacts within the spaced apart, -a cylinder associated alsace? and agrappling tool attached to the lower end ot the string or pipe and run into the well and en- The drawing and description disclose what is ,f

. now considered to be a preferred form of the invention by way of illustration only, while the broad principle oi' the invention will be deiined by the appended claims.

, yWhat E claim is:

l. A pipe perforator comprising a body, explosive cartridges therein. projectiles in the body aligned with the cartridges, a source of electrical energy associated with the body and adapted to be lowered with the body into a well. electrical conductors leading from said source through-the charges of the cartridges and means operable in lcontinuous sequence by well liquid pressure for successively completingelectrical circuits through the conductors whereby the lcharges will be ignited. Y

2. A pipe'perforator shaped to be lowered into ranged to be lowered with the body into the wel! and operable by,v the liquid pressure outside of the body and edective to successively ilre -said 3. A a well and comprising abody, radially directed projectiles on the body, explosive charges arranged, when exploded, to eject the projectiles,v electrical means arranged to be actuated by pressure of the well liquid and eifective to successive-` ly ignite said charges, said means including a series of xed contacts and a movable contact arl be actuated by said pressure.

well and comprising aperforator body, radially directed projectiles anchored therein; explosive charges arranged, when exploded,

to eject th projectiles, a

sourceoi electrical energy associated with the body and arranged to be lowered into the well with the body, electrical conductors connected with the source and including heatarranged to ignite the respective charges, a housing connected to the body, spaced contacts in the housing'connected with said con\ ductors, a switch element and means arranged to be actuated-by the pressure of, the well liquid to move said switch element into contact with said spaced contacts successively tccomplete the electrical circuits through the respective heating; I

elements in continuous sequence.

-5. A perorator shaped to be lowered into a well and comprising a perforator body, radially directed projectiles located therein, explosive charges arranged, when exploded, to eject the projectiles, a source of electrical energy arranged the well, 'electrical conductors connected with the source and including' heating elements arranged to ignite the respective charges, a housing associated with the housing and with the heus-` ing, a plunger therein,

respective electrical may be completed cylinder having an contacts. whereby* circuits through said conductors, said inlet channel through which A, liquid under pressure'in the well'may be exerted 6. A pipe perforator comprising a body shaped Eil a contact tongue movable I with the plunger into successive contact with the to be lowered into a. well and having aliquid channel, a radially directed projectile carried by the body. and an explosive charge arranged when ignited, to project the projectile, electrical means arranged to be actuated by the pressure ci the liquid in the well to complete anv electrical cir cuit whereby the charge will be ignited, a frangible closure for said passageway normally preventing the actuation of the electrical means by said pressure. I

7. A pipe perforator shaped to be lowered into a well and comprising a body. a radially directed 'projectile therein, an explosive charge arranged to eject the projectile and electrical means arplosive cartridge therein, a projectile in the body 5 aligned with the cartridge, a source of electrical energy associated with the body and adapted to be lowered with the body into the well, an electrical conductor leading from said source to the charge of the cartridge and means operable by 10 well liquid pressure for completing an electrical circuit through the conductor whereby the charge will be ignited. e Y

WALTER L. CHURCH. 

